Stop-cock



UNITED STATES PATENT OFFICE.

DAVID N. B. COFFIN, JR., OF LYNN, MASSACHUSETTS.

STOP-COCK.

Specification of Letters Patent No. 12,195, dated January 9, 1855.

To all 'Lu/wm it may concern Be it known that I, DAVID N. B. Cor- FIN, Jr., o-f Lynn, in the count-y of Essex and State of Massachusetts, haveinvented a new and useful Self-Closing Stop-Cock, of which the'following is a full, clear, and exact description, reference being hadto the accompanying drawings, which make part of this specification, andin which- Figure l represents a vertical longitudinal section o-f thecock; Fig. 2 represents a vertical transverse section of the samethrough the valve at the line a' of Fig. l, and Fig. 3 represents ahorizontal section of the cock thro-ugh the line if: n/T': of Fig. l.

It has long been a desideratum to obtain for the pipes that supply anddistribute water in cities, a stop cock, simple in construction,durable, and cheap, whose valve can be readily opened by hand, and willclose of itself when the hand is withdrawn, and thus prevent the wastewhich results from carelessly leaving hydrants open.

It is the main object of my invention to supply this desideratum.

The cock represented in the drawings, does not differ materially in itsexternal form and proportions from ordinary cocks. It has a chamber tocontain the valve and its seat, which chamber communicates by one tubecalled the shank of the cock, wit-h the pipe, cistern, or other sourceof supply of the liquid to be drawn oii, and by another tube called thenozzle, with the open air, or the receptacle into which the liquid is tobe discharged. The valve seat and the valve (a) are for the purpose ofopening and closing the communication between these tubes through thechamber (i), so as to establish a current of the liquid through the cockfro-m the source of supply and to cut off the same at will.

The valve chamber is cylindrical and has its upper end closed by a screwgland (d), which serves the purposes of guiding the valve stem,permitting the same to protrude through the side of the cock, and oflcompressing an elastic packing of india rubber, or other suitablematerial tightly around the valve stem, and against the sides of thechamber to prevent leakage, and also to support the packing against thevalve, in order to press the same constantly toward its seat.

The valve (a) is, in this example, cylindrical, and is itted into thechamber so as `to* slide freely toward and vfrom its seat (n).

with increased power to return the valve to its seat.

The upper extremity of the valve stem is jointed to the central part ofa disk, cap or foot, whose edges (r) project considerably beyond thesides of the stem, and rest upon the top of the gland (d). From theupper side of this foot a handle (h) projects upwards, and stands erect,when the valve is closed. By inclining this lever any way in which thejoint will allow it to turn, the valve will be raised; but as the pointat which the stem is jointed to the foot is always considerably on oneside of the point, on which the edge of the foot rests, there is nothingto prevent the valve from being closed by the pressure of the springwhenever the hand of the operator is removed from the handle (71,)therefore, the cock will be in no danger of standing open, except whenintentionally held so.

. I have described a vulcanized india-rubber packing, as I have triedthat substance and found it to answer a good purpose, but I haveno doubtthat many other elastic substances or springs, simple or compound mightbe employed for the purpose, and would answer very well.

Having thus described my improved stop cock, what I claim therein as myinvention and desire to secure by Letters Patent is--v 1. Thearrangement of a rocking lever substantially as herein described, sothat if turned either way by the hand, it will open the valve and be insuch a positionthat when the hand is removed, the valve will be free toclose by the pressure of the spring.

2. I also claim the arrangement of theV DAVID N. B. ooFFIN, JR.Witnesses `A. R. COFFIN,

WILLIAM WIII'IIINE. l

